import java.util.HashMap;
import java.util.Map;

public class Test01 {
    public static void main(String[] args) {
        Map<String,String> m=new HashMap<>();
        m.put("郭靖","黄蓉");
        m.put("韦小宝","小龙女");
        m.put("伊志平","沐剑屏");
//        System.out.println(m);
//        String value=m.put("韦小宝","双儿");
//        System.out.println(value);
//        System.out.println(m);
//        String result=m.remove("郭靖");
//        System.out.println(result);
//        System.out.println(m);
//        m.clear();
        System.out.println(m);
        boolean KeyResult=m.containsKey("郭靖");
        System.out.println(KeyResult);
        boolean ValueResult=m.containsValue("小龙女");
        System.out.println(ValueResult);
        boolean result=m.isEmpty();
        System.out.println(result);
        int len=m.size();
        System.out.println(len);




    }
}
